Device and method for heat and mass-exchange between gas and liquid

ABSTRACT

A device for heat, mass, and chemical exchange and interaction between gases and liquids. Nozzles feed the gas at angles in different directions to form a gas-liquid mix, swirls, and/or foam above an array of such nozzles.

RELATED APPLICATIONS

This application claims priority to U.S. Provisional Application No.61/898,713, filed Nov. 1, 2013, which is incorporated herein byreference in its entirety.

FIELD OF THE INVENTION

This invention is related to chemical, metallurgical, energy, and otherindustries, involving heat, mass and/or chemical exchange andinteraction between two fluids, such as a gas and a liquid, for example,for removing dust and chemical contaminants from gases. It can used as ascrubber, an absorber, a desorber, heat exchanger, or a chemicalreactor.

BACKGROUND OF THE INVENTION

Russian Patent RU 2132220 describes a device that uses dust collectingapparatus with a cylindrical housing and a blade swirling devicecreating a vortex along a vertical axis of the housing. A swirlingdevice is arranged in an aerodynamic cavity and is sprinkled with water.The water is delivered directly onto swirler blades from a plate filledwith water with slots on edges. A ring deflector is installed in anupper part of the cavity under which a row of flat-spray water feednozzles is arranged. The device provides 99.5-99.9% cleaning of gasesfrom dust at the resistance to air flow of 1200-1300 Pa and a specificconsumption of reflux water of 0.1-0.15 l/nm. The indicatedcharacteristics are provided due to high efficiency of water and gasdistribution over the swirler's perimeter; the recirculation of water(pulp) in the swirler providing several-fold increase in active zonewatering; washing of cleaned gases before a drop trap by clean feedwater; installation of high efficiency drop trap of hood-type withcorner members arranged over screw line. The device delivers enhancedefficiency of gas cleaning.

Russian Patent RU 2104752 describes devices for trapping of toxicantsfrom gaseous effluents in emulsified flow of liquid used in powerengineering, metallurgy, chemistry, and other branches of industry. Theadapter is made in the form of a parallelepiped with an axial vaneswirler secured in its bottom part and made of four vanes having theshape of obtuse triangles, whose obtuse angles are inscribed in thedihedral angles of the parallelepiped. The middles of the bases toucheach other in one point lying in the parallelepiped axis. Windows areprovided just above the vanes in the parallelepiped walls, initiators ofemulsification in the form of four plates having the shape of righttriangles also inscribed in the dihedral angles of the parallelepipedand decreasing its flow section by 10 to 25% are positioned above thewindows.

The known foaming gas washers or plate gas washers used for cleaninggases of dust, of gaseous contaminants, etc. comprise a horizontal platewith holes or slots. When an irrigating liquid is dripped onto the platefrom above and a gas is fed from below, turbulent foam is formed wheregas bubbles are continuously created, merged, and destroyed. Such platesare usually made with holes 4-8 mm in diameter or with slots 4-5 mmwide. The number of holes or slots is chosen so that the ratio ofcumulative cross-section area of holes or slots to the total area of theplate is 0.15-0.25.

SUMMARY OF THE INVENTION

The invented device has a high efficiency of gas, heat, and chemicalexchange, reaction, and interaction between a gas and a liquid, ishighly reliable, and inexpensive for both manufacturing and operation.

The grid plate is configured so that the jets of the gas intended forcleaning are not vertical, but rather sloping in a variety ofdirections. These jets intersect and interact to form above the gridplate a gas-liquid mix, such as foam. The jets' intersections cause arapid increase in the relative speeds of the gas and liquid dropletswithin these jets. This improves the efficiency of the heat and massexchange between the gas and the irrigating liquid, even when the slotsor openings in the grid plate are relatively large (for example, whencompared with prior art devices).

There is a variety of specific configurations of the grid plates forforming jets sloping in different directions. The effect of improvedinteraction between the gas and the liquid is greatly pronounced for theplates providing the jets in the directions significantly far of thenormal to the grid plate and with directions as close as possible to theplate surface being the most advantageous for a given ratio of openings'(or slots') cumulative cross-section to the total area of the gridplate. A plate forming gas jets sloping in various directions may be aperforated sheet where the openings or perforations are shaped to causethe passing gas to form a sloping jet, or an array of parallel swirlingnozzles with blades, or an array of slots constructed, for example, ofangular elements.

One embodiment of the present invention is an apparatus comprising ahousing comprising an inlet and an outlet for passing a fluid along afluid path in the housing from the inlet to the outlet; a plurality ofnozzles arranged in a grid, the grid being disposed inside the housingin the path of the fluid; each nozzle comprising a three-dimensionalstructure with a plurality of axial swirler blades disposed inside thethree-dimensional structure, each swirler blade being a tiltedquadrangle, each quadrangle having two adjacent sides in contact withtwo adjacent sides of the three-dimensional structure, and eachquadrangle having two other adjacent sides intersecting at a same realor imaginary vertex on a vertical axis of the quadrangle. The fluidpassing inside the housing can be a gas. The apparatus further comprisesan inlet for supplying an irrigating liquid to the housing, the inletfor supplying being disposed along the fluid path after the grid andbefore the outlet. The tilted quadrangle can be a tilted rectangle,which also can be curved. The three-dimensional structure of theapparatus can be a parallelepiped.

In one embodiment of the invention each nozzle of the grid isconstructed to swirl the gas in one direction. The nozzles in the gridcan be arranged in the grid in parallel.

In yet another embodiment of the invention the grid can be comprised ofa plurality of fastening elements, wherein each fastening element isdisposed in the imaginary vertexes of the plurality of nozzles.

In yet another embodiment of the invention at least a portion of eachedge of each side of the three-dimensional structure is cut in such away that at least the portion of each edge does not protrude beyond oneof the two adjacent sides of the quadrangle in contact with thethree-dimensional structure.

The method of the present invention comprises supplying a fluid throughan inlet to enter a housing and passing the fluid along a fluid path;passing the fluid through a plurality of nozzles arranged in a grid, thegrid being disposed inside the housing between the inlet and the outlet;forming a plurality of intersecting streams from the fluid as the fluidpasses through gaps formed by adjacent axial swirler blades of theplurality of nozzles; supplying an irrigating liquid into the housingfrom above the grid through at least one inlet and causing the pluralityof intersecting streams and the irrigating liquid to mix above the grid;wherein each nozzle of the plurality of nozzles comprises athree-dimensional structure with a plurality of axial swirler bladesdisposed inside the three-dimensional structure, each swirler bladebeing a tilted quadrangle, each quadrangle having two adjacent sides incontact with two adjacent sides of the three-dimensional structure, andeach quadrangle having two other adjacent sides intersecting at a samereal or imaginary vertex on a vertical axis of the quadrangle.

The fluid supplied through the inlet can be a gas. The working speed ofthe gas along the fluid path can be about 5 m/s. The nozzles arearranged in the grid in parallel. The invention contemplates that eachnozzle can swirl the gas in the same direction.

In yet another aspect of the invention supplying the irrigating liquidinto the housing through at least one inlet occurs without usingspraying jets. At least one inlet is disposed along the fluid path afterthe grid and before the outlet.

In yet another aspect of the method of the present invention the gridfurther comprises a plurality of fastening elements, each fasteningelement being disposed in the imaginary vertexes of the plurality ofnozzles.

In yet another aspect of the invention a nozzle for forming a grid, thenozzle comprises a three-dimensional structure and a plurality of axialswirler blades disposed inside the three-dimensional structure; eachswirler blade being a tilted quadrangle having a first pair of adjacentsides and a second pair of adjacent sides; the first pair of adjacentsides being in contact with adjacent sides of the three-dimensionalstructure; and the second pair of adjacent sides intersecting at a samereal or imaginary vertex on a vertical axis of the quadrangle; whereineach two adjacent swirler blades of the plurality of axial swirlerblades form a gap in such a way that a stream of fluid exiting that gapintersects with another stream of fluid exiting an adjacent gap.

The nozzle can further comprise a fastening element disposed in theimaginary vertexes of the nozzle. Furthermore, at least a portion ofeach edge of the three-dimensional structure of the nozzle is cut insuch a way that at least the portion of each edge does not protrudebeyond one side of the first pair of adjacent sides of the quadrangle incontact with the three-dimensional structure.

Still other objects and aspects of the present invention will becomereadily apparent to those skilled in this art from the followingdescription wherein there are shown and described preferred embodimentsof this invention, simply by way of illustration of the best modessuited for to carry out the invention. As it will be realized by thoseskilled in the art, the invention is capable of other differentembodiments and its several details are capable of modifications invarious obvious aspects all without departing from the scope of thesubject application. Accordingly, the drawings and description will beregarded as illustrative in nature and not as restrictive.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings incorporated in and forming a part of thespecification, illustrate the present invention, and together with thedescription serve to explain the principles of the invention.

FIG. 1 shows schematically the gas flowing through a one-stage device.

FIG. 1a shows schematically the gas flowing through a two-stage device.

FIG. 2a shows an example of a plate grid.

FIG. 2b shows the plate grid with arrows for the gas jets formed by thenozzles.

FIG. 2c shows an example of a plate grid formed by multiple instances ofthe plate grid shown in FIG. 2 a.

FIG. 2d shows the grid plate formed by multiple instances of the plategrid shown in FIG. 2a with arrows for the gas jets formed by thenozzles.

FIG. 3a shows a quadrangular axial swirling nozzle with four blades.

FIG. 3b shows the quadrangular axial swirling nozzle with four blades ofFIG. 3a with arrows for the gas jets formed by the nozzle.

FIG. 3c show a grid plate composed of nine nozzles of FIG. 3 a.

FIG. 4a shows another quadrangular axial swirling nozzle with fourblades.

FIG. 4b shows the quadrangular axial swirling nozzle with four blades ofFIG. 4a with arrows for the gas jets formed by the nozzle.

FIG. 4c show a grid plate composed of nine nozzles of FIG. 4 a.

FIG. 5 shows grid plate composed of nine nozzles of FIG. 3a or FIG. 4awith arrows for the gas jets formed by the nozzles.

FIG. 6a shows a hexagonal axial swirling nozzle with six blades.

FIG. 6b shows the hexagonal axial swirling nozzle with six blades ofFIG. 6a with arrows for the gas jets formed by the nozzle.

FIG. 6c show a grid plate composed of seven nozzles of FIG. 6 a.

FIG. 6d shows grid plate composed of seven nozzles of FIG. 6a witharrows for the gas jets formed by the nozzles.

FIG. 7a shows a cross-section of a slotted grid plate composed ofangular elements.

FIG. 7b shows the slotted grid plate of FIG. 7a with arrows for the gasjets formed by the slots.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present device provides efficient heat and mass exchange between agas and a liquid, while being highly reliable and coast efficient interms of capital and operating costs.

FIG. 1 schematically shows an embodiment of the present invention in thehousing 3. A gas is supplied through a gas inlet 1 to pass through agrid plate 6, though a gas-liquid mix 2 and into a gas outlet 4. Theliquid, such as water, is injected into the gas-liquid mix 2 from anozzle 5 positioned above the grid 1. The liquid passing downwardthrough the grid 6 is drained through a drain 7.

The gas is moving though the device, for example, by being pressure-fedthough the inlet 1 and/or by being sucked out though the outlet 4. Thepressure differential may be created by a fan, so that the gas movesupward through the grid plate 6. The liquid from the nozzle 5 irrigatesthe grid plate 6. No provisions for spraying the liquid are necessaryfor the device.

The grid plate 6 is composed of nozzles (made of plastic, metal, etc.),such as shown in FIGS. 2a-2d, 3a-3d, 4a-4c , 5, 6 a-6 d, and 7 a-7 bcreating intermixing jets of gas forming turbulent flows, swirls, and/orother non-linear flows of gas in the gas-liquid mix 2 for efficientmixing and interacting with the liquid supplied above the grid.

The nozzles comprising opening or slots in the grid 6 form gas jetshaving different directions. The liquid from the nozzle 5 is captured bythese jets (preferably near their nozzles) and forms droplets. The gasjets form an interwoven structure above the grid as shown in theexamples in FIGS. 2d , 5, 6 d, and 7 b, however the invention is notlimited to these specific examples of jet configuration, other anglesand other forms and positions of jets are possible as well. As the gasjets intermix, the relative speeds of the gas and the liquid dropletswithin the gas jets increase dramatically. This dynamics of the flowwithin the jets also provides uniformity of distribution of the liquidabove the grid and intermixing of the gas and liquid over the grid 6along the entire cross-section of the housing without need for sprayingof the irrigating liquid by the nozzle. This results in non-linear (forexample, turbulent) flows within a resulting gas-liquid mix, which canbe foam. This gas-liquid mix has very high area of gas-liquid contactper volume. This mix renews quickly and is uniform. This improves theefficiency of the heat and mass exchange even when the opening or slotsare relatively large compared with the prior art devices. In oneembodiment the gas flow through the inlet pipe is at about 5 m/s whilethe flow through the nozzles in the grid plate is about 15-30 m/s.

The mixing of the gas jets passing through the opening or slots in thegrid 6 with the liquid, such as water, supplied from the nozzle 5 takesplace above the grid 6, rather than on it. This reduces the wear of thegrid and prolongs its usefulness.

When the gas and the irrigating liquid enter the device through theinlet 1 and the nozzle 5 respectively, the liquid begins to accumulatein the gas-liquid mix layer (or foam) 2. The height of this layerincreases until the upward gas pressure of the gas passing through theopenings or slots in the grid is balanced by the weight of thegas-liquid mix layer above the grid. Subsequently, the amount of liquidsupplied from the nozzle 5 would correspond to the amount of liquidpushed under the weight of the gas-liquid mix down through the grid'sslots or openings into the bottom part of the housing 3. Effects ofdroplets escaping with the gas and vapor through the outlet 4,evaporation and condensation of the liquid must also be accounted forwhile feeding the liquid into the device through the nozzle 5. Theremainder of the discharged liquid is transferred from the devicethrough the drain 7.

FIG. 1a shows a two-stage embodiment of the present invention, where asecond grid plate 6 a is positioned above the grid plate 6. The liquidsupplied from the nozzle 5 above the second grid plate 6 a interactswith the gas within the gas-liquid mix 2 a above the second grid plate 6a. The liquid then drips through the second grid plate 6 a downward tointeract with the gas above the grid plate 6 within the gas-liquid mix2.

Generally, in two-stage or multiple stage devices, comprising two ormore grid plates one above the other, the irrigating liquid is fedthrough the nozzle 5 onto the top grid plate 6 a and the primaryaccumulation of liquid takes place in the gas-liquid 2 a mix above thetop grid plate 6 a. After accumulating within the gas-liquid mixture onthe bottom grid plate, the liquid drains into the bottom part of thehousing 3 and is transferred from the device through the drain 7. Thegas to be cleaned is fed through the gas inlet 1, and the cleaned gas isremoved through the gas outlet 4.

The distance between the grid plates may be 0.4-0.6 m. The counterflowin the device shown in FIG. 1a reduces the required amount of liquid forcooling of gases and/or purifying of gases at high concentration ofcontaminants. In such cases, the ratio of cumulative cross-section areaof openings or slots to the total area of the grid plate may beincreased for the bottom grid plate compared with other grid plates. Forthe gases hotter than 250° C. this increase is about 20%; for the gaseshotter than 400° C. this increase is about 30%; etc.

Instead of a gas shown in FIGS. 1-1 a, any fluid, such as a liquid, maybe used generally in the same way.

Instead of a liquid shown in FIGS. 1-1 a, any fluid, such as gas(especially a gas that is heavier than air), may be used generally inthe same way.

FIG. 2a shows an example of a grid plate shaped as a plate with threenozzle perforations for use in the devices shown in FIGS. 1-1 a. Eachnozzle in this plate is shaped as a pyramid with a triangular base. Eachpyramid is missing the base face and one of the side faces. The threeidentical pyramids are positioned symmetrically around the plate center22 at a 120° angle to each other. Other perforations with slopingelements extending downwards are possible.

FIG. 2b shows (as arrows) gas jets flowing upward through the nozzles inthe plate shown in FIG. 2a . These gas jets form an upwardly movingswirl within the housing 3.

FIG. 2c shows an example of a grid plate shaped as a plate with multiplenozzle perforations for use in the devices shown in FIGS. 1-1 a. Eachnozzle in this plate is shaped as a pyramid with a triangular base. Eachpyramid is missing the base face and one of the side faces. The pyramidsare grouped in threes, and each such group is positioned symmetricallyaround its respective center on the plate at a 120° angle to each other.

FIG. 2d shows (as arrows) gas jets flowing upward through the nozzles inthe plate shown in FIG. 2c . These gas jets form an upwardly movingswirl within the housing 3. These jets cross, interact, and intermix toform upwardly moving swirls.

FIG. 3a shows an example of a quadrangular swirling nozzle 30 forforming grids 6 and/or 6 a in the devices shown in FIGS. 1-1 a. Thenozzle 30 comprises four blades 311, 312, 313, and 314 to form four jetsof gas. The corners of the blades meet at a point 32. Each blade isquadrangular with a uniform curvature in one dimension. The curvature ofeach blade is around its respective axis passing though the point 32 andnormal to one of the sides of the nozzle 30. One such axis is shown as adashed line 33. The blades 311 and 312 form a gap δ1, the blades 312 and313 form a gap δ2, the blades 313 and 314 form a gap δ3, and the blades314 and 311 form a gap δ4.

FIG. 3b shows as arrows four gas jets formed by the nozzle 30 shown inFIG. 3a . Each jet is passing through one of the gaps δ1-δ4.

FIG. 3c shows an example of a grid plate 35 composed of nine swirlingnozzles 30. The grid plate 35 is regular and uniform to form a uniformdistribution of liquid within the gas-liquid mix above the grid plate35.

The gas jets formed by the openings or slots in a grid plate can bequite abrasive. Therefore, it is useful to minimize the number and sizeof the structural elements these jets impact above the grid plate.Otherwise these elements would not only interfere with the jetformation, but also would be subject to much wear. However, above theblades in the nozzle at the central axial locations the abrasive effectmay be minimal. These locations may be used for axial rods or otherstructural elements, for example, for attaching the grid plate of itscomponents.

FIG. 4a shows an example of a quadrangular swirling nozzle 40 forforming grids 6 and/or 6 a in the devices shown in FIGS. 1-1 a. Thenozzle 40 comprises four blades 411, 412, 413, and 414 to form four jetsof gas. The lines along the edges of the blades meet at a virtual point42. Each blade is quadrangular and flat. Each blade is tilted around itsrespective axis passing though the virtual point 42 and normal to one ofthe edges of the nozzle 40. One such axis is shown as a dashed line 43.The upper edges of the swirling nozzle 40 are in line with edges of theblades. The nozzle edge a is in line with an edge of the blade 411, thenozzle edge b is in line with an edge of the blade 412, the nozzle edgec is in line with an edge of the blade 413, the nozzle edge d is in linewith an edge of the blade 414. A hollow sleeve 45 (for installation andattachment purposes) is positioned along the center vertical axis of thenozzle. The blades 411 and 412 form a gap δ1, the blades 412 and 413form a gap δ2, the blades 413 and 414 form a gap δ3, and the blades 414and 411 form a gap δ4.

FIG. 4b shows as arrows four gas jets formed by the nozzle 40 shown inFIG. 4a . Each jet is passing through one of the gaps δ1-δ4.

FIG. 4c shows an example of a grid plate composed of nine swirlingnozzles 40. The grid plate is regular and uniform to form a uniformdistribution of liquid within the gas-liquid mix above the grid plate.The sleeves are installed on the rods 46.

FIG. 5 shows as arrows crossing jets of gas mixing with liquid above agrid plate composed of sixteen swirling nozzles 30 or 40. Each jet isformed by one of the swirling nozzles. Each swirling nozzle forms fourjets, as shown in FIGS. 3b and 4 b.

FIG. 6a shows an example of a hexagonal swirling nozzle 60 for forminggrids 6 and/or 6 a in the devices shown in FIGS. 1-1 a. The nozzle 60comprises six flat blades to form six jets of gas in a way similar to aquadrangular swirling nozzle 40 shown in FIG. 4 a.

FIG. 6b shows as arrows six gas jets formed by the nozzle 60 shown inFIG. 6a . Each jet is passing through one of the gaps between theblades.

FIG. 6c shows an example of a grid plate composed of seven swirlingnozzles 60. The grid plate is regular and uniform to form a uniformdistribution of liquid within the gas-liquid mix above the grid plate.

FIG. 6d shows as arrows crossing jets of gas mixing with liquid above agrid plate composed of seven hexagonal swirling nozzles 60 with sixblades each. Each jet is formed by one of the swirling nozzles. Eachswirling nozzle forms six jets, as shown in FIG. 6 b.

FIG. 7a shows a cross-section of a slotted grid plate composed ofangular elements for the devices shown in FIGS. 1-1 a. The angularelements 711 with an angle α point downwards. The angular elements 712with an angle β point upwards. The aerodynamic resistance of such aplate is reduced when β is less than α, so that gaps δ are uniformlynarrowing in upward direction. However, the angles α and δ may be equalas well. The arrows show gas jets formed by a gas passing through thegaps δ.

FIG. 7b shows as arrows crossing jets of gas mixing with liquid abovethe slotted grid plate of FIG. 7 a.

The advantages of the devices according to the present invention includevery high tolerance to low quality of the irrigating liquid (includingin terms of the size and percentage of mechanical impurities) while atthe same time being highly efficient of interaction of the irrigatingliquid with the gas being purified; this greatly reduces the costs ofchemicals used as well as the costs of storing and supplying thesechemicals. For example, to reduce or neutralize acidic gases one may uselime wash without prior filtering of sand, which is always present inlime in nature.

This high efficiency allows using grid plates with openings, as shown inFIG. 2a-2d , and on gaps δ1-δ4 (on FIGS. 3a-3d, 4a-4c, and 6a-6d ) ofabout 15-40 mm and even larger and slots 10-20 mm wide and even larger;the ratio of cumulative cross-section area of openings or slots to thetotal area of the grid plate is 0.15-0.3.

In a device according to this invention used for filtering ashes from acoal smoke 99.5% of ashes were captured. The output of purified gas at170° C. was 20,000 m³/hour. The dimensions of the device were about 1.5m×1.6 m×2.5 m. The hydraulic pressure of the fed gas did not exceed 1.9kPa. The irrigating liquid was water circulating within a close contourbetween the device and a simple ash precipitator. The concentration ofparticles in the water used for irrigation was between 3% and 5%, whichis unacceptably high for most other types of systems used for thispurpose.

Another device according to this invention was used for removing HCNfrom the air used to ventilate leaching chambers for gold ore. Theoutput was 12,300 m³/hour. The absorption of HCN was 94%-96% with inputconcentration of 0.2-0.4 g/m³. The irrigating liquid was a watersolution of unfiltered lime milk with a high content of sand pebbles ofup to 5 mm in size. This solution cannot be used for most other types ofsystems used for this purpose.

In both cases the grid plate was an array of quadrangular swirlingnozzles as shown in FIG. 4a ; each nozzle being 100×100 mm in size andproducing gas jets at 71° angle off the vertical. The ratio ofcumulative cross-section area of openings to the total area of the gridplate was 0.227. In the first device the grid plate was composed of 135such nozzles, in the second device the grid plate was composed of 81such nozzles.

The swirls from the nozzles are usually contained within 20 mm above thegrid plate, while further above the motion of gas and of gas-liquid mixis turbulent and/or chaotic and/or forms a foam.

The foregoing description of preferred embodiments of the subjectapplication has been presented for purposes of illustration anddescription. It is not intended to be exhaustive or to limit the subjectapplication to the precise form disclosed. Obvious modifications orvariations are possible in light of the above teachings. The embodimentwas chosen and described to provide the best illustration of theprinciples of the subject application and its practical application tothereby enable one of ordinary skill in the art to use the currentapplication in various embodiments and with various modifications as aresuited to the particular use contemplated. All such modifications andvariations are within the scope of the subject application as determinedby the appended claims, when interpreted in accordance with the breadthto which they are fairly, legally and equitably entitled.

What is claimed is:
 1. A device for mixing fluids, comprising: ahousing; a substantially upward path for a first fluid; a plurality ofnozzles forming a substantially two-dimensional grid across the path forthe first fluid to pass through the grid; and an injecting nozzlepositioned above the grid for a second fluid into the path above thegrid; wherein the plurality of nozzles forming a substantiallytwo-dimensional grid comprise a three-dimensional structure with aplurality of axial swirler blades inside the three-dimensionalstructure; wherein the nozzles are shaped and positioned within the gridso as for the first fluid passing through the grid to form within thepath above the grid for each of the plurality of nozzles at least onejet of the first fluid, wherein a mixing layer is formed above the grid;for a plurality of the jets to interact to form within the path abovethe grid non-linear flow of the first fluid; and for the non-linear flowof the first fluid to contact and interact within the path above thegrid with the second fluid injected into the path, wherein the firstfluid and the second fluid are mixed within the mixing layer above thegrid.
 2. The device of claim 1, wherein the non-linear flow of the firstfluid comprises at least one substantially upwardly flowing swirl. 3.The device of claim 1, wherein the plurality of nozzles are shaped andpositioned within the grid so as for the first fluid passing through thegrid to form within the path above the grid for each of the plurality ofnozzles jets of the first fluid; for a plurality of the jets from theplurality of nozzles to interact to form within the path above the gridnon-linear flow of the first fluid; and for the non-linear flow of thefirst fluid to contact and interact within the path above the grid withthe second fluid injected into the path.
 4. The device of claim 3,wherein the non-linear flow of the first fluid comprises substantiallyupwardly flowing swirls.
 5. The device of claim 4, wherein the swirlsare rotating in substantially same direction.
 6. The device of claim 1,wherein the first fluid is gas.
 7. The device of claim 1, wherein thesecond fluid is liquid.
 8. The device of claim 1, wherein the nozzlesare slots.
 9. The device of claim 8, wherein the nozzles are slotsnarrowing upwards.
 10. The device of claim 8, wherein the nozzles areparallel slots.
 11. The device of claim 1, wherein the nozzles areperforations with sloping elements extending downwards from the grid.12. The device of claim 1, further comprising the nozzles forming asubstantially two-dimensional second grid across the path for the firstfluid to pass through the second grid; wherein the injecting part for asecond fluid into the path is above the second grid; and wherein thenozzles are shaped and positioned within the second grid so as for thefirst fluid passing through the second grid to form within the pathabove the second grid for each of the plurality of nozzles at least onejet of the first fluid; for a plurality of the jets to interact to formwithin the path above the second grid non-linear flow of the firstfluid; and for the non-linear flow of the first fluid to contact andinteract within the path above the second grid with the second fluidinjected into the path, wherein the first fluid and the second fluid aremixed within the mixing layer above the grid.